Solute Meets Solvent

Why it matters

Stir a spoon of sugar into a glass of water and it vanishes — but it is still there! You have just made a solution, one of chemistry's neatest tricks.

Predict first

When you dissolve a little sugar in a lot of water, what do we call the water?

The substance that dissolves is the solute (sugar). The one it dissolves in — usually the larger amount — is the solvent (water). Together they make a solution.

• The solute
• The solvent — correct
• The mixture only, with no special name
• The residue

What you do

Add a small amount of sugar (the solute) to a large amount of water (the solvent) and stir to build a sugar solution. Notice which part is the larger quantity.

Check yourself

In a sugar solution, which statement correctly names the parts?

The solute is the substance that dissolves (sugar), the solvent is the liquid it dissolves into (water), and the uniform mixture they form is the solution.

Common salt is stirred into water until it disappears. What kind of mixture is the salt water?

When salt dissolves evenly in water you cannot see it any more, and it forms one uniform (homogeneous) liquid — that is a solution.

In most solutions, how does the amount of solvent compare with the amount of solute?

A small amount of solute usually dissolves in a much larger amount of solvent. That is why in sugar water the water (solvent) is the bigger quantity.

• Sugar is the solute, water is the solvent, and the sweet liquid is the solution — correct
• Sugar is the solvent and water is the solute
• Both sugar and water are called solutes
• The mixture is called a residue
• A solution — correct
• A suspension you can filter
• A pure substance
• A compound
• The solvent is usually present in the larger quantity — correct
• The solute is always present in the larger quantity
• They must always be equal in amount
• There is no solvent in a solution